The present invention relates to a grapple structure and more specifically relates to an improvement in the grapple structures disclosed in U.S. Pat. Nos. 3,620,394 and 3,667,796 respectively issued to Symons et al and Funk respectively on Nov. 16, 1971 and June 6, 1972.
The grapples disclosed in the above-identified patents are both of a type including a pair of opposed arcuate tongs having upper end portions interconnected through means of a pair of cross link assemblies and an extensible and retractable hydraulic actuator. The tongs of the patented structures are suspended from a swivel joint through means of a pair of suspension link assemblies having respective lower ends connected to the pair of tongs so as to share the pivotal connection of a respective end of one of the cross link assemblies with a tong, and respective upper ends connected to a universal connector joined to an output shaft of the swivel joint.
It has been found that the above-described grapple structure is not entirely satisfactory since the points of connection of the actuator and the cross and suspension link assemblies are so related that the actuator undergoes substantial vertical movement during its actuation for opening and closing the grapple tongs. This movement is underside since it requires that a pair of hoses connected undesirable the swivel joint and the actuator for supplying fluid to and exhausting fluid from the actuator be of sufficient length to accommodate the movement. These relatively long hoses have parts which project outwardly in the area below the swivel joint and above the grapple tongs and are thus vulnerable to being damaged by being struck by or coming into contact with trees or the like during operation of the grapple structure.